/Engine/Source/Runtime/Engine/Public/Net/OnlineEngineInterface.h
Unregister a given player from the online session
virtual void UnregisterPlayers ( [UWorld](API\Runtime\Engine\Engine\UWorld) * World, [FName](API\Runtime\Core\UObject\FName) SessionName, const [TArray](API\Runtime\Core\Containers\TArray)< [FUniqueNetIdWrapper](API\Runtime\CoreOnline\Online\FUniqueNetIdWrapper) > & Players )